My research interests include examining how animals adapt to environmental (temperature changes) and metabolic (exercise, feeding, etc.) perturbations to their acid-base status. Alterations in breathing are the primary, acute response to a metabolic acidosis or alkalosis. Current projects in my lab involve experiments designed to understand how central (brainstem) chemoreceptors sense changes in blood gases and pH. We use the combined techniques of fluorescence imaging microscopy and whole-cell electrophysiology to measure neuronal responses to changes in CO2, O2, and pH in brainstem neurons. I am interested in understanding how these chemoreceptors are altered by changes in the animal's environment.

Selected Publications:

Santin, J.M. and Hartzler, L.K. (in press). Respiratory signaling of locus coeruleus neurons during hypercapnic acidosis in the bullfrog, Lithobates catesbeianus.  Respiratory Physiology & Neurobiology.

Reinert, B.L., Pohlman, R.L., and Hartzler, L.K. (2012). Correlation of Air Displacement Plethysmography with Alternative Body Fat Measurement Techniques in Men and Women. International Journal of Exercise Science 5(4): 367-378.

Sheehan, K.M. and Hartzler, L.K. (2011).  Effects of XS® Energy Drink on Aerobic Exercise Capacity of Athletes.  International Journal of Exercise Science 4(2): 152-163.

Gargaglioni, L.H., Hartzler, L.K., Putnam, R.W. (2010).  The locus coeruleus and central chemosensitivity.  Respiratory Physiology and Neurobiology 173(3): 264-273.

Kersh, A.E., L.K. Hartzler, K. Havlin, B. Hubbell, V. Nanagas, A. Kalra, J. Chua, R. Whitesell, N.A. Ritucci, J.B. Dean and R.W. Putnam. (2009). pH regulating transporters in neurons from various chemosensitive brainstem regions in neonatal rats. Am. J. Physiol. Regul. Integr. Comp. Phsyiol. 297(5): R1409-20.

Hartzler, L.K., Putnam, R.W. (2009). Central Chemosensitivity in Mammals. In Cardio-Respiratory Control in Vertebrates: Comparative and Evolutionary Aspects. Eds. M.L. Glass and S.C. Wood. Springer-Verlag, Berlin, Germany.

Hartzler, L.K., Dean, J.B., and Putnam, R.W. (2008). The chemosensitive response of neurons from the locus coeruleus (LC) to hypercapnic acidosis with clamped intracellular pH. In Integration in Respiratory Control: From Genes to Systems. Advances in Experimental Medicine and Biology 605: 333-337.

Nichols, N.L., Hartzler, L.K., Conrad, S.C., Dean, J.B., and Putnam, R.W. (2008). Intrinsic chemosensitivity of individual nucleus tractus solitarius (NTS) and locus coeruleus (LC) neurons from neonatal rats. In Integration in Respiratory Control: From Genes to Systems. Advances in Experimental Medicine and Biology 605: 348-352.

Hartzler, L.K., Munns, S.L., Bennett, A.F., and Hicks, J.W. (2006). Metabolic and blood gas dependence on digestive state in the Savannah monitor lizard Varanus exanthematicus: an assessment of the alkaline tide. J. Exp. Biol. 209: 1052-1057.

Hartzler, L.K., Munns, S.L., Bennett, A.F., and Hicks, J.W. (2006). Recovery from an activity-induced metabolic acidosis in the American Alligator, Alligator mississipiensis. Comparative Physiology and Biochemistry Part A 143: 368-374.

Munns, S. L., Hartzler, L. K., Bennett, A. F. and Hicks, J. W. (2005). Terrestrial Locomotion does not constrain venous return in the American alligator, Alligator mississippiensis. J. Exp. Biol. 208: 3331-3339.

Munns, S. L., Hartzler, L. K., Bennett, A. F. and Hicks, J. W. (2004). Elevated intra-abdominal pressure limits venous return during exercise in Varanus exanthematicus. J. Exp. Biol. 207 (23): 4111-4120.

Kemper, W.F., Lindstedt, S.L., Hartzler, L.K., Hicks, J.W., and Conley, K.E. (2001). Shaking up glycolysis: sustained, high lactate flux during aerobic rattling. PNAS. 98 (2): 723-728.

Stinner, J. N.; Hartzler, L. K. (2000). Effect of temperature on pH and electrolyte concentration in air-breathing ectotherms. J. Exp. Biol. 203 (13): 2065-2074.

Stinner, J. N.; Hartzler, L. K.; Grguric, M. R.; Newlon, D. L. (1998). A protein titration hypothesis for the temperature-dependence of tissue CO2 content in reptiles and amphibians. J. Exp. Biol. 201 (3): 415-424.